At various times, workmen use different types of hand tools such as screwdrivers, chisels, awls, and the like. These types of implements have become standard instruments in performing specific work tasks such as driving screws into a work piece or chiseling away undesirable material. There are occasions, however, in which a workman uses a number of different tools to complete a task. For example, the workman may need to alternately use a straight edge screwdriver and a Philips screwdriver. In order to address such situations, a number of multi-purpose tools have been developed. Multi-purpose tools not only provide versatility and time savings, but usually save on tool storage space.
Many types of multi-purpose tools have been developed. There are tools in which a plurality of working tips are freely stored within a handle. For example, U.S. Pat. No. 3,683,984 to Hull and U.S. Pat. No. 4,227,430 to Jansson disclose storing replaceable bits in longitudinal grooves formed in the outside of a handle. With these tools the desired tip is selected and taken from its storage compartment and manually placed in its working position. In most cases, the working tip must be secured in its working position by a spring-loaded detent, locking screw, chuck, or magnet To exchange the working tip being used for another working tip, the securing means must be disengaged before the working tip being used may be removed. Once it is removed, a new working tip may be positioned and secured in the working position. If the workman must change between various working tips, he must repeat the procedure of engaging the securing means, removing the working tip, replacing the working tip with another working tip, and then re-engaging the securing means. When a magnet is used as the securing means, it is possible for the tip to bind on the work piece and pull out of the tool as the tool is withdrawn.
Other types of multi-function tools have avoided time-consuming and frustrating problems created by having a plurality of working tips which must be attached or detached to the tool. Such tools typically position and secure the working tip in its operating position by some mechanical means which is manually operated without manually removing and handling the working tip. Examples include tools disclosed in U.S. Pat. No. 438,150 to Glover and in U.S. Pat. No. 1,816,812 to Allison. Glover and Allison position the working tip over a stationary chute which directs the working tip into its operative position. When the working tip is aligned with the chute, the tip is released and drops into its operating position and is appropriately secured. Unfortunately, these designs still require manipulation of a set screw or chuck to lock the working tip in position.
U.S. Pat. No. 4,572,038 to Graham discloses is a tool having a cylinder assembly containing a plurality of tips. As the cylinder is rotated, each of the tips is aligned with a stationary chute. A drive shaft, coupled to a handle, engages the tip and pushes the tip through the chute to an operative position. Unfortunately, Graham's working tips cannot be replaced without destroying the tool. Thus, the tools usefulness diminishes as tips break. Moreover, unless a particular tool has all of the different types and sizes of working tips that a user needs, the user needs more than one tool.